A simulation investigation the performance of a small scale Elliptical Savonius wind turbine with twisting blades and sloping ends plates

Savonius wind turbine is among of simplest type of vertical axis wind turbines to produce the power from wind. Elliptical blades one of adopted geometry to design the Savonius turbine rotor. One of the most important measures to improve the performance of elliptical Savonius turbine rotor by developing the blade geometry. In this study, a CFD simulation used to investigate the effect of geometrical parameters of the small scale elliptical Savonius turbine rotor (ESTR) with inner surface wavy blades. The simulation has been implemented in a in a two configurations design models, ESTR models with twisting angle in range of (5˚ to 45˚) and ESTR models with tilt angle of end plates (3˚ to 15˚) with a constant Aspect ratio of 1 and overlap ration of 0.2. The performance evaluation were in terms of power coefficient and torque coefficient as a function of tip speed ratio. The numerical results show that an increase in the maximum power coefficient with increase of twist angle and tilt angle until optimum values of 30˚ and 12˚ for the twist angle and tilt angle, respectively. Although in all configuration show a good increase in power coefficient but there are a significant increasing in maximum power coefficient for ESTR model with twist angle of 30˚ which was 3.7% while the increasing reach to 14.55% at ESTR model with tilt angle 12˚ at tip speed ratio of 7. As well as, these two models provide a jump in power coefficient for a different range of tip speed ratio compare to previous model of ESTR

CFD Investigation of Empty Flanged Diffuser Augmented Wind Turbine

Enclosing a wind turbine within a Flanged diffuser is an innovative mean to increase the power harvested by turbine blades and it is among the most effective devices for increasing wind turbine energy. The geometric parameters of the empty flanged diffuser contribute efficiently to increase mass flow in the diffuser, hence improve the turbine performance. The study presents developed models of the geometrical parameters of an empty flanged diffuser that suitable for a scaled-down (1-6.5) horizontal axis wind turbine, the geometry parameters were involved the diffuser length, diffuser angle, flange height and flange angle. The geometrical models were verified and CFD investigated in 2-D and 3-D domains. Results obtained from CFD simulations show that when using a compact size of flanged diffuser within optimum geometrical parameters can give well acceptable for flow velocity increase at suggested place for the turbine rotor install where the increase in flow velocity is due to lower pressure at the outlet of the diffuser. As there is also a significant effect of the flange angle on increasing the flow velocity inside the diffuser where the rate of increase in wind velocity at turbine position was calculated for two flange angles (0 ÌŠ and 5 ÌŠ ) . In another hand, the results also provided information on the velocity contours and velocity streamlines around diffuser geometry

Experimental and Simulation Investigation of Performance of Scaled Model for a Rotor of a Savonius Wind Turbine

Renewable energy sources are preferred for many power generation applications. Energy from the wind is one of the fastest-expanding kinds of sustainable energy, and it is essential in preventing potential energy issues in the foreseeable future. One pertinent issue is the many geometrical alterations that the scientific community has suggested to enhance rotor performance features. Hence, to address the challenge of developing a model that resolves these problems, the purpose of this investigation was to determine how well a scaled-down version of a Savonius turbine performed in terms of power output using a wind tunnel. Subsequently, the effect of the blockage ratio produced in the wind tunnel during the chamber test on the scaled model was evaluated. This study discusses the influences of various modified configurations on the turbine blades’ torque and power coefficients (Cp) at various tip speed ratios (TSRs) using three-dimensional (3D) unsteady computational fluid dynamics. The findings showed that the scaled model successfully achieved tunnel blockage corrections, and the experimental results obtained can be used in order to estimate how the same turbine would perform in real conditions. Furthermore, numerically, the new models achieved improvements in Cp of 19.5%, 16.8%, and 12.2%, respectively, for the flow-guiding channel (FGC at Ⴔ = 30°), wavy area at tip and end (WTE), and wavy area on the convex blade (WCB) models in comparison to the benchmark S-ORM model and under identical wind speed conditions. This investigation can provide guidance for improvements of the aerodynamic characteristics of Savonius wind turbines

CFD investigation of empty flanged diffuser augmented wind turbine

Enclosing a wind turbine within a flanged diffuser is an innovative mean to increase the power harvested by turbine blades and it is among the most effective devices for increasing wind turbine energy. The geometric parameters of the empty flanged diffuser contribute efficiently to increase mass flow in the diffuser, hence improve the turbine performance. The study presents developed models of the geometrical parameters of an empty flanged diffuser that suitable for a scaled-down (1-6.5) horizontal axis wind turbine, the geometry parameters were involved the diffuser length, diffuser angle, flange height and flange angle. The geometrical models were verified and CFD investigated in 2-D and 3-D domains. Results obtained from CFD simulations show that, using a compact size of flanged diffuser within optimum geometrical parameters can give well acceptable for flow velocity increase at suggested place for the turbine rotor install. The increase in flow velocity is due to lower pressure at the outlet of the diffuser. As there is also a significant effect of the flange angle on increasing the flow velocity inside the diffuser where the rate of increase in wind velocity at turbine position was calculated for two flange angles (0 ̊ and 5 ̊). In another hand, the results also provided information on the velocity contours and velocity streamlines around diffuser geometry